Measuring apparatus.



G. H1. GIBSON.

MEASURING APPARATUS.

APPLICATION FILED FEB. I. Ism.

Patented Oct. 24, 1916.

3 SHEETS-SHEET 1.

A TTORNE Y 1H iff I el l/ "I FTI' m ||I|| ""1 'lI H Il IIIIII I. II'II I I :"III; IJNI IIiI- III'H i IIII :IIIII mq INVENTOR 254 MM WITNESSES G. H. GIBSON.

MEASURING APPARATUS.

APPLICATION meu FEB. l. |911 3 SHEETS-SHEET 2.

Patented oet. 24,1916.

G. H. GIBSONU MEAsumNG APPARATUS.

Patented Oct. 24, 1916.

3 SHEETS-SHEET 3 IN VEN TOR ATTORNEY WITNESSES WW UNrTED STATES PAprENr oFFroE.

GEORGE H. GIBSON, OF MONTCLAIR, NEW JERSEY, ASSIGNOR 'IO JOSEPH S. LOVERING WHARTON, WILLIAM S..HAL LOWELL, 'AND JOHN C. JONES, ALL 0F PHILADELPHIA, PENNSYLVANIA, DOING BUSINESS AS FIRM OF HARRISON SAFETY BOILER WORKS.

MEAsUIr-.ING APPARATUS.

Specification of Letters Patent. Patented Oct, 1/916 Application led February 1, 1911.l Serial No. 605,878.

vMeasuring Apparatus, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

My present invention comprises novel vmeans for determining the rate of iow of a llquld over a Weir by means responsive to V the varlatlons 1n hydrostatic pressure occurring on the supply side of the weir. and thereby determining the variations in height ofthe liquid ,level on that side of the weir,

said height varying in accordance with,v

known laws as the rate of flow over theweir changes; and .in its more specific aspects the present invention consists in the novel and effective means which I have devised-for measuring the rate of flow through a closed Weir chamber associated with, 'and receiving the discharge from an openl water heater,

as disclosed and claimed in my prior Patent Number 1,015,556, granted January 23rd In its broader aspects, however, the invention consists in fluid flow measuring apparatus not'- limited to use in such apparatus as is claimed in my prior patent to' whiehfreference has been made. j

In carrying out my invention, I employ a pressure chamber in which the pressure varies as, or in a determined-relation with' the variationsinthe iuid pressure which it is desired to measure, and provide said chamberwith a. movable wall portion, which may be in the form of a flexible 'diaphragm -or the like, and provide means for balancing'the outwardly acting force of vthe fluid within the pressure chamber on the movable wall thereof. y

In so `far as I have just specified, the

pressure responsive apparatus does not diffrom that before known but my present -lnvention includes provisions for so adjusting the intensity of the force opposing "the action of the-internal iiuid pressure ythat-'the f movable 4wallfpo'rtiori'is mantainedgat all times- `in,Isubstantially the same position re- 'gardle'ssV ofthe variations in'internal pressure, instead of being allowed to occupy difkferent positions depending upon the lintenweir.

pressure chamber in the same position as the pressure in it varies, substantially Aincreases the sensitiveness of the apparatus and the accuracy of the results obtained.

' In addition to the features above mentioned, my invention embodies-various novel 'features of construction and arrangement hereinafter described and claimed.

For .a general understanding of the invention and`its advantages, reference should be vhad to the accompanying drawings and y descriptive matter in which I have illusvtratdand-described several forms of apparatus embodying features of my invention. Of the drawings, Figure 1 is an elevation partlydiagrammatic and partly inv section of apparatus for measuring the water heated by the direct action of steam in an open water heater. Fig. 2 is a sectional elevation of aV portion of the apparatus employed iin. Fig. 1 taken on a largerscalethan that of Fig. 1. Fig. 3 is a partial-sectional eleva-- tion of a ,Weir construction, which may Lbe employed as, or in lieu of that shown in-Fig. 1 and embodies vprovisions for Avaryingjthe' we ir notch angle to compensate for temperature variations. in the water flowing` over the.

shown in Fig. 3.` Fig. 5 is a partial elevation taken similarly toFig.` 3 but on a largerl Scale. Fig. 6 is a sectional elevation of pressure measuring appara-tusv differing from Fig. 4 is 'a plan of the apparatusl 90" that shown in Figs. 1 and 2;. Fig. `7 isa partial elevation with parts broken away .95 and in section of a portion of the weir chai- I ber illustrating a modiication of a portion.:V of the pressure transmitting systemshown in Fig.' 1. Fig. S is a view taken. similarly 1 to Fig. 7 showing a thirdform of apparatus.

Fig. 9 is aview taken similarly to-'Fig V7" A showing a fourth form of apparatus.l Fig. y 10 is a sectional elevation of a-portion .of

the apparatus shown in Fig`.y7. .FigQll isfa f diagrammatic representation; of a"'n1o`diiedl` form of a portion o t-the apparatus ,shown in Fig. 1. 4

` Referring irst.4 to the apparatus shown in Fig. 1, A represents the body portion or tank of an open feed water heater, which in con-I` 5 A represents the water spreading trays A2 the water distribution box and A3 the perforated plate supporting coke or other suitable purifying and ilteringmaterial A2. A5 represents the overflow discharge orifice through which the excess water heated in the heater is discharged. B represents the cold water supply pipe. C represents the pipe supplying steam for heating the water. C is an o1 s eparator of common form. D represents the overflow box intowhich the port A5 opens and into which the oil and other impuritiesdrain from'the separator C. D2 is a waste pipe leading from the box D and controlledby a valve operated, as is usual, by aioat (not shown) in the box D.

In the form shown inthe drawings, the measuring box or- Weir receptacle E is secured to the side of, and forms a part of a unitarystructurewith the heater tank A.

partments E and E2 by the weir -E3 which doesnot extend to the top of the rece tacle, and preferably has thel ,notch or ori ce E4 formed in its upper edge, as best shown in ig. 3. Y represents a steam' pipe connection for equalizing the pressure inthe steam space of the'tank A and receptacle E. F represents the service dischargeI connection from ithe compartment E2. The discharge port A6 of tank A opens directly into the lower end'of the' compartment E. The supply of water to the -tank A is controlled in response to the accumulation of water in the compartment E2 by means of a valve VG2 in the water supply pipe'B, the valve being openedv and" closed by a float G in the float box G. The latter is in communication with the compartment E2 and the valve G2 is opened andjclosedas the water` level in c ompartment'*I*]2f"falls'k 'below or rises toa predeterminedheight. A Withjth's apparatus vthe-height level in the Icom' artmentiE 'above lofthe apex` ofjt e weirfnotch E, in accordance with fayknownlaw with the variations in 'the rate.` ofow of water lfrom the compartmentv E E2. The 'variations in'heightof the water level in compartment E measured andthe rate of the level static pressure in the chamber E at a determined level below the normal surface ofthe liquid. To accomplish this, with the appara- The receptacle E is divided into two com,

',automatically, which of water will vary l into' thei compartment may-bjindirectly iow determined by'.` means responsive to the'variations in'hydrov tus ofFig. '1, a vertical pressure tube H is 1 `extended' into' the compartment E" with its'fl` located at a distance from the Weir receptacle E and need not be at the 'same level therewith. The pressure chamber J may be formed in various ways. As shown in Figs.

-l and 2, it comprises a body portion J connected to brackets -X and X2 extending from a suitable support or base X. The pressure chamber body J is in the shape of a shallow cup, and the movable wall portion thereof is formed by a flexible disk J 2, of any suitable material, such as soft copper which is detachably secured at its periphery to the body J by the externally threaded ring J 3, suitable packing rings J 4 being provided to insure tight joints. The disk J2 has formed on it, or secured to it at its center a projection J5 which is pivoted to a lever L, pivoted at its lower end on the projection X1 of the bracket X. Various provisions may be made for exerting the varying force upon the lever L necessary to balance the outward thrust upon the lever exerted by the diaphragm J2 without permitting any substantial movement of the diaphragm. In Fig. 1, I have illustrated an arrangement for accomplishing this purpose includes a tension spring an electric motor for adjusting the tension of the spring, and electric circuit connections by which the motor is caused to increase or decrease the'tension of the spring upon slight movements inv one direction or the other of the lever L. As shown in Fig. 2, the lever L extends through the bracket X2 which is slotted and to its upper end a yoke L is pivotally connected at L2. A threaded rod L3 forms an extension of the yoke L which may be adjusted by means of the nut L4. A tension spring M connects the rod L3 and thereby the lever L to a tension adjusting member N. The latter is in the form of an apertured plate having guide extensions N and N2 sliding through brackets X8 projecting from the base member X.` Within the j aperture in the member N, is located a cam lio transversely to the plane of movement of they l member N and through the member N takes the .pull of the spring M. The shaft O has secured to it agear wheel O2 which meshes with and is driven by the worm P carried by the shaft of the electric motor P. The latter is supplied with current from a suitable source as the batteryl Q, connected be- `tween one terminal P3 of the motor and the v P2 and 'P4 --are connected by suitable conductors, lone' to leverjL, the other motor terminals an adjustable contact Q lever L and thel other. adjustable 'contact yQ2 atone side of the to the corresponding at the other side of the lever L. "The arrangement is such that a Y fvery slight movement ofthe lever L to the left 'will close a circuit, including thebatthe shaft O, and thereby increase the ten sion of the spring M and move the lever L out of engagement with the contact Q2.

lVhere, as in the apparatus shown, the vapor pressure acting on the upper surface of the liquid in the compartment E. .is not necessarily the same as the atmospheric pressure acting on the outer side of the diaphragm J2, it is essential for accurate results that this should be compensated for, and in the apparatus disclosed, I. employ for this purpose a pressure chamber K which may be in all respects similar to the pressure chamber J and comprise parts K', K2, K3,

K4 and K5, like the parts J to J5 inclusive respectively. Iy secure the chamber K to the brackets X and X2 with the projection K5 in line with the projection J 5 and facing the opposite side of the lever L from that faced'by the projection J5. The interior of the pressure chamber K is connected by a pipe I and the extension I thereof to the interior of the' receptacle E above the water level therein. In the arrangement shown in Fig. 1, I have the tubes H and I both filled with a liquid, as water, and subject' both tubes, so far as possible, to the saine temperature conditions as by arranging them side by side and in close proximity to each other.y To avoid inaccuracies, which might be caused by the presence of air or lother gases in the pressure chambers J and K and in the pipes leading thereto, I preferably provide means, such as the cocks J7 and K7 to facilitate the removal of air from the pressure chambersl and the conduits and the filling of these chambers and conduits with the desired liquid. These cocks open to the corresponding pressure chambers J` and K at their highest points. lWhere the chambers J and K are located at or above the level of the connections H and 'I, I preferably depress the pipes H and I adjacent the members H and I, so that any air passing into the tubes H and I from receptacle El will tend to accumulate at the upper ends of said members, and small cocks H2 and I2 may be provided through which the accumulated air mav be blown out from time toI time, very readily with the apparatus disclosed in which the steam pressurewithinthe chamber 'E is usually above the `atmospheric amount of heated water supplied to boilers, for instance, the weight and not the volume of the liquid flowing is the quantity primarily wanted, and with the presentv apparatus, the operation depends upon the relation between the liquid pressureyon the supply side of the Weir at the level of the weirl apex and the amount of the liquid flowing. The relation between H, the-height in 'inches of a column of liquid, P the hydrostatic pressure at the bottom of the column .110 in pounds per square inch and D the weight of a cubic inch of the liquid', is expressed by the formula:

pressure. The pipe Sections H3 and I3, immediately adjacent the cocks H2 and I2, and the pipe ysectionsvJ .and K6 between the cocks JT and KT, and the chambers J and K, may advantageously be made of glass, so that air accumulating therein may be visually detected. To maintain the pipe I full .of water,I may, provide a water seal at its lower end. This may be obtained by means of `the cup-like extension I3, formedat the lower end ofthe pipe I and constantly' supplied with water by condensation of the steam inthe steam space of the compartlnent E.

The general laws governing the 'flow of 8o A highly accurate and gen- In the formula just given V is the How in .i

cubic feet per minute, H is the height in inches of the water level on the supply side of the Weir above the apex of the lweir notch, and 0 is the angleof the Weir notch.

For many purposes, as in determining the 1j f "D y y 1,15 -From this formula and the first given formula V= .316 t "I'Pml n 2 l v l 120, `the following formula may beobtained by -s'imple substitution;

' 546.048 am. P2418- :xH-n?- In the last given formula YV, (equal to 1728 V D) is the number of pounds of liquid flowing per minute.

If the conditions be such that in the .for-

mula just given, W and P are the only variables, it is apparent that by giving the cam O the proper contour, and those skilled in the art will understand how this may easily be done, the angular movements of the shaft O lmay be proportional to the changes inthe quantity W, while at the same time, the changes in the tension of the spring M, resulting from such movements, are pro- ;portional `to. the corresponding changes in I), so that the angular position of the cam O and of the shaft O, at any instant, will correspond directlyto the number of pounds of water then flowing per minute. Those skilled in the art will understand that the l actuating the hands"coperating with the disk R3 of the registering mechanism, and the clock mechanism R2 which drives the counting train.v i I- havenot thought it necessary lto illustrate the means by which the arm O3 adjusts the gearing connecting the clock 'mechanism with the counting wheels' proper for the reasonthat it forms no part of my invention `and for the further reason that quantity kexhibiting arrangements for this generalppupose have-long been known. One form of mechanism for this purpose, which I refer to merelyv by way of example is shown in Patent No. 84,476 granted to Chameroy, December l, 1868.

The weight of a unit volume of liquid, such as` water, is, in general, dilferent at different temperatures. In order, therefore, that a given pressure at the bottom of the pressure tube H may always correspond to a. given rate of flow in pounds per minute, it is essential to compensate or correct. for

the change in density of the liquid flowing producedby changes in temperature. One way of accomplishing` this is so to change the angle of the Weir as the temperature of the water changes, that the quantity D Lm remains constant. j Results sufficiently correct for all ordinary practical purposes may be obtained with the type of apparatus dis- A.closed by employing provisions, including a simple thermostatic arrangement for increasing and decreasing the weir angle as tan.

Vstrip E,

the temperature of the water decreases and increases` In the particular form of apparatus shown in Figs. 4 and 5 for adjusting the Weir notch angle as the temperature of the water varies, the weir notch proper is formed by two weir edge strips and E of suitable material, such as brass, which are mounted on, and overlap the margin of the notch E4 formed in the weir E3 proper. The plate E6 is secured directly to the` weir E3 proper,-as by rivets E14 and the strip E is formed with an undercut socket E* concentric Iwith the apex E10 of the weir notch, and in this socket is received the chamfered circular extension E'I of the weir edge strip Ev The, latter fits snugly against the weir E3, the adjacent surfaces being carefully ma- .chined to restrict leakage and in addition to being held in place by the pressure of the waterA -on` it, one or more rivets E14, (one being shown) may be secured to the The rivet E, shown, passes through a slot E12 in the weir E3 and has an enlarged head which bears against the discharge side of the weir E3. To automatiycally turn the weircdge strip E5 about the *apex El?, any suitable thermostatic mechanism may beemployed. In the conventional form illustrated the 'thermostatic mechanism Z comprises a U-shaped member Z anchored at its bottom as by'rivets Z4b to the Weir E3. To the ends of the legs of the mem' ber Z are secured the ends of the legs of a U-shapedf'member Z2, and, 4to the bottom of the latteris secured one end of a rod Z3. The'upperend of the rod Z3 is secured to the weir edge;l strip E5 as by the rivet Z5.

v The"|. J-shaped member Z2 is formed of some material, such as iron, having a relatively small coeficient ofexpansion, and the members Z and Z3 are formed of material lsuch as zinc, having a relatively large coefficient of expansion. In consequence the edge strip E5 is turned about the apex E10 toward and away from thevstrip EB as the temperature of the water rises and falls, and by properly proportioning the parts. the angle of the weir may thus be varied to the extent necessary to obtain a close approximation to the theoretical change in flow re quired to insure a rate of flow with a given hydrostatic pressure at the mouth of the tube H Which does not vary with the tempe'rature of the water.v

It is of course apparentthat with the Weir adjusting apparatus disclosed, the angle of the portion of the notch formed wholly in the strip E5 is not-varied by moving .that strip, but as this portion of the notch is small, and since in general, only a small fraction of the total flow takes place through it, Ithe fact that this portion of the weirv notch is not varied as the rest of the weir notch does not appreciably ai'ect the accuracy of the results obtained with the apparatus. I make no claim herein, however, to means for adjusting a Weir to compensate for variations in temperature and density of liquid flowing over the Weir, except in connection with the particular form of' measuring apparatus disclosed herein, for while I believe myself to have been the first to provide means for making adjustments to compensate for the variations in the temperature of the liquid flowing through them, such arrangements, in their general and may be connected to similar tension ad-y aspects form the subject matter of my Patent No. 1,048,677, granted December 31,

1912, on a co-pending application, filed ofI l sponding tothe tubes H and I of the con-- even date herewith. y

It will be understood, of course, that thev invention disclosed herein in its general aspects is not dependent upon the particular form of, or arrangement of pressure cham- 1 bers employed, and in Fig. 6, I have illustrated an arrangement in which the pres'A sure chambersJA and KA, adapted to bel employed in the same way as the pressurev chambers J and K respectively, above def scribed, are formed by expansible bellows J1 and K1 respectively which are placed `end to end and connected by an interposed rigid but movable diaphragm or common head -L1., At their opposite ends the bellows J1o and K1"l are connected to rigid stationary diaphragms or heads J11 and K11. The diaphragm L10 is extended and has connected to it bythe rods L11 a crosshead L12 to which is adjustably connected a member L14. To the member L1'-1r is secured one end of a tension spring which may be similar to the spring M'of -the first described construction,

justing means. In this fornrof the invention, the contacts Q and Q2 may be arranged on opposite sides of an extending portion of the' diaphragm L10.

While, for most purposes I prefer to employ suitable automatic provisions for' adjusting the force necessary to balance the force of the fluid pressure in the pressure measuring apparatus, it is sometimes advantageous, as plicity, to manually adjustl the balancing force. One arrangement for accomplishing this is shown in Fig. 11, this arrangement differing from that of Fig. 1 primarily in the substitution of `a hand wheel P2 for the motor P, which with its circuit connec tionsis done away With.` ThekleverkL'infw Fig. 11 has a pointer QextensionILfWwhmh registers with the line Tf1 when""lever:.lf

is in the neutral position. f r

Vith the f1 apparatus shown will be apparent that thegchanges-,in density,

of the water filling the :pressure-chambers' J and K, conduits'H andI, tube I, and the portion-of the tube water inthe cup I? from the standpoint of sim-- H above the level ofthev will not affect the" re'- sults obtained by the measuring apparatus, it being assumed that the temperature` conditions in each pressure chamber and all parts of the various conduit connections thereto, are the same as for the other-pressure chamber and the corresponding conduit connections to it. The change in den sity, consequent upon changes in tempera-v ture of the column of water in the tube H- below the level of the water in the cup I3 may,` however, result in slight errors in the readings of the apparatus. This may be avoided in various ways. One arrangement by which such error is avoided is shown in Fig. 7:, Where the tubes H10 and I1 corre- Ahorizontally at the same level, and with` the pipef H10 opening at its underside, as indicated at H11, at the level of the Weir notch apex. The' tube I1 is formed with an upstanding extension lformed by concentric tubes 111, 112 and I, of materials having dierent coeflicients of thermal expansion, so chosen that the distance between the upper end `of mouth 1114 of the vertical extension of tube I1o and the level of the orifice H11 varies inversely With the density ofv the water filling it as the latte'rva'ries in tem-v perature. This results in securing va hydrostatic pressure With the tube I1 at the level of the orifice H11, Whichis constant and independent of the temperature. of the water. Instead of having the condults running lod from the pressure 'chambers to the Weir chamber, open to the latter, as in Figs. 1 and`.

7, these conduits 'may lbe sealed and the pressure transmittedpthrough vflexible dia'- phragms. One`arrangement lofvthis character is' illustrated in Fig. .8 wherein the tubes H20 and I2", corresponding to the tubes' f H and I of Fig. 1 have connected to their ends Within the Weir chamber lpressure chambers H21v and `I 21, Whiclrm'ay be like `the pressure chambers .Iv and K. The pressure chamber H21 has its flexible diaphragm horiz'ontal and 'at thelevel of the Weir notch apex, chamber 12,1 is above the Water level. This arrangement avoids the errors which result from the accumulation of air in pipes normally filled with liquid, and the tubes `H2o and I20 may be connected directly to the H and I- of pressure transmitting pipes l such'a system as 1s shown in Fig. 1. l Thevr .fluid within the pressure chambersH21 and .111 and the spaces connected thereto, may be air lor, other suitable gas. or water, oil, or`

kother suitable liquid. This arrangement fhas an advantage over that of Fig. 1 also that the fluid employed in the pressure Whilethe diaphragm of the pressure y i of liquid freezing in any within the tubes H30 and I30 chambers and connected pipes may be of such character that there is no possibility portion of the pressure transmitting system.

In the form of apparatus shown in Figs. 9 and l0 the tubes H30 and I3, corresponding to the tubes H andl I of Fig..1,may enter the weirchamber, as in Fig. l, and may be open at their inner ends to the interior of said chamber. In this form, however, no water seal is provided at the lower end of thetube I30 and the entire pressure transmitting system instead of being filled with water is filled entirely with air. To maintain the pressure transmitting system full of air I provide means for injecting air into the system 'continuously but slowly with the result that the air constantly escapes in minute quantities from the tubes H30 and 13 at their openV ends into the weir chamber, and in consequence, the air pressures respectively, correspond exactly to the hydrostatic pressureat the lower end of the tube H30 and to the vapor pressure above the water level in the weir chamber. vide air in minute streams to the interiors of the tubes H30 and 113 in the particular form of apparatus illustrated, I connect these tubes to the pressure transmitting| pipes H and I by fittings IV. Each fitting W contains a diaphragm NVS, or the like, formed with a fine passage W4 through which air under pressure, supplied by a pipe IV from a suitable air reservoir W2, compressor, or

the like, .may slowly leak. This type of apparatus has anumber of advantages. With it no errors result from small leaks, into or out of any'portion of the pressure transmitting system. There is no possibility, of

course, of trouble through freezing of the pressure transmitting fluid. The differences in pressure 1n the pressure chambers of the pressure measurmg apparatus, due tolvariations in temperature conditions of the air in anyportion of the pressure measuring system, are ofcourse, much smaller than where the fluid in the pipes is a liquid. In general, however, H and I in this form of the invention, arranged side by sidev and in close proximity so as to be subjected to the same temperature conditions, at least as to the vertical portions thereof. e l

lVhile in acordance with the provisions of the statute Ihave illustrated the best forms of my invention now known to me, it will be apparent to those skilled in the art that many changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention,and that in some cases, Some of the features of my in.- vention may be used with advantage without a corresponding use of other features.

Having'now described my invention, what To continuously pro-v ysions whereby I prefer -to have the pipes level in said chamber on and below the normal liquid level on the supply side of the -`weir therein, means for exerting a force upon said movable Vmember in the opposite dlrection proportional to the pressure 1n said chamber above the liquid level therein and ow exhibiting means responsive to the difference between the said forces exerted 011 said movable member.

2. Apparatus for measuring the rate of vflow of a liquid, comprising a weir chamber, a. weir contained therein, a pipe leading from the weir 'chamber on the supply side of the weir at a determined level below the normal liquid surface level on that side of the Weir, a second pipe leading from said weir chamber above the normal liquid surface level therein, a pair of pressure chambers connected, one to one of said pipes and thevother to the other of said pipes and each having a, movable wall portion and proviinternal pressure on the movable wall 4portion of cach chamber opposes the corresponding thrust on the movable wall portion of the other chamber, and fiow exhibiting means responsive to the difference between said thrusts.

3. flow of a liquid, comprising a weir chamber, a weir contained therein, a pipe leading from the weir chamber on the supply side of the weir at a determined normal liquid surface level on that side of the weir, a second pipe leading from said Weir chamber above the lnormal vliquid surfac'elevel therein, a pair of pressure chambers connected, one to one of said pipes, and the -..other to the other of said pipes, and each having a movable wall portion and provisions whereby the outward thrust of the internalk pressure on the movable wall portion of each chamber opposes the corresponding thrust on the movable wall portion ofthe other chamber, and flow exhibiting means responsive to the difference bethe normal liquid surface level on the supply side of said Weir.

the outward thrust of the 9 Apparatus for measuring the rate of level below the 5. Apparatus for measuring the rate of flow of a liquid, comprising in combination, a weir chamber, a weir over which the liquid flows contained therein, and flow exhibiting means responsive tothe liquid pressure at a determined level on, and below the normal liquid surface level on the supply side of said weir, said means including rectifying provisions and a. member moved thereby proj:nationally to the changes in the rate of liquid liow occurring on variations in the pressure measured.

Apparatus for measuring the rate of flow of a liquid, comprising in combinatioi'i an adjustable weir. over which the liquid flows and means for measuring the hydrostatic pressure `at a determined level below the nornial liquid surface level on the supply side of said weir, and tlierinostatic means for adjusting said wcir to decrease the flow over the weir for a given height of liquid level on the supply side thereof, as the temperature of the liquid flowing increases.

T. Apparatus for measuring the rate of flow of a liquid, comprising in combination a wcir having means whereby the notch may be adjusted, over which the liquid flows and means for measuringr the hydrostatic pressure at a determined level below the normal liquid surface level on the supply side of said weir, and means for adjusting the weir to decrease the tlow occurring with a given height of liquid level on the supply side thereof as the temperature of the liquid flowing increases.

8. Apparatus for measuring,r the rate of flow of a liquid, comprising in combination a weir, formed `with a V-notch through which the liquid flows, andhaving the' sides ofsaid notch -relatively adjustable, thermostatic meansy for causing said sides to approach and recede from each other as the temperature of the liquid flowing rises and falls, and means for measuring the hydrostatic pressure at a determined level on, and below the normal liquid surface level, on the supply side of said weir.

9. Apparatus for measuring the -ate of flow of a liquid of varying temperature including in .combination a closed weir chamber and a weir contained therein, pressure measuring apparatus comprising a pressure tube opening downward into said weir chamber-at a determined level on, and below the' normal liquid lsurface level on, the supply side of'said weir, means for slowly injecting a gaseous Huid into Said tube at a rate sufficient to insure av relatively slow discharge through the tube into said chamber and How exhibiting means responsive to the gaseous pressure thus maintained in said tube.

10,. Apparatus for measuring the rate of tlow of a liquid comprising a'closed weir 35 chamber and a Weir contained therein, a

tube opening downward into the chamber on the supply side of the yweir at a determined level belowa the normal liquid surface level on the supply side of the weir, a second tube opening into said chamber above the normal surface level of the liquid therein, means for slowly injecting air into each tube whereby the air pressure within the said tubes at the points where they open to said chamber correspond,in the one case to the hydrostatic pressure at said determined level and in the other case to the vapor pressure above the thereon of the pressure within the chamber,

said means comprising a spring, and a movable cam for adjusting the tension of the spring, said cam having such a contour that thechanges in spring tension, and the movements of the cam producing them, are propoi-tional respectively to the corresponding changes in hydrostatic pressure, and to the changes in the rate of flow of the liquid over the weir. 'i

l2. Apparatus for measuring the flow ofl a liquid, comprising in combination a weir over which the liquid flows, a pressure chamber having a movable wall, provisions for maintaining a pressure therein proportional to the pressure at a determined level below the normal liquid surface level on the supply side of the weir, means for exerting a force on said movable wall opposing the outward thrust thereon of the pressure within the chamber, including provisions for adjusting said force to maintain said wall in' a substantially fixed position, and for indicating the 'amount of said force, comprising a` mov- 'able cani' and a cooperative movable member said cam having such a contour that its movements and the 'corresponding movements of Said member are proportional, one to the changes in the rate of flow of the liquid over the weir, and the other to the corresponding changes in pressure in saidY chamber.

13. Apparatus for measuring the flow of a liquid comprising in combination a Weir over which the liquid flows a pressure cham-` bei` having a movable wall`v provisions for maintaining a pressure within said chamber proportional to the( pressure ata determined level below the normal liquid surfacelevel on the supply side ofthe Weir, means for exertin a. force on said movable Wall opposing t e outward thrust of the pressure within the chamber, including provisions for adjusting said force to maintain said wall in a substantiallyfixed position, said means and provisions comprising a spring, a shaft, a cam carried by the latter and connections between saidcam and said sprin whereby the rotation of the shaft varies t e tension 10 of the spring, saidvcam having such a con- Coplas Ao! this patent may be obtained for ave cents each, by addressing the to the corresponding changes in pressure in 15 said chamber.

.o GEO. H. GIBSON.

Witnesses: y

FRANK S. BRoADHURsT, WILBERT SAILER.

Commissioner ot Patenti,

Washington, D. C. 

